158 ROMANCE OF LOW LIFE AMONGST PLANTS. 



sometimes lunate, and attenuated towards each end. 

 A paler transverse band crosses the centre of the 

 frond, and the ends are usually occupied by a clear 

 space containing active granules (Fig. 28). They vary 

 in size according to the species. At the present time 

 they arc^universally accepted as algae, reproducing 



themselves by zygospores, resulting 

 from conjugation. Ehrenberg, how- 

 ever, regarded them as belonging 

 to the animal kingdom, for the 

 following reasons, viz. "Because 

 they enjoy voluntary motion, they 

 have apertures at their extremities, 

 they have projecting permanent 

 organs near the apertures, which 

 are constantly in motion, and they 



at the end. The arrows ;„_..„„„„ K 1 • j. 1 . 



indicate the direction of mcicase by hoiizoutal spontaneous 



surface circulation. j;. ,:„:„„ >> ta T\;r i /. 



division. Dr. Meyen, who was of 

 the opposite opinion, contends that " their structure is 

 exactly similar to that of the Confervae, their forma- 

 tion of fruit and the development of the fruit also 

 like that of the Confervae. The occurrence of starch 

 in the interior, with which they are frequently nearly 

 filled, is a striking proof of their being plants ; they 

 have no feet, for what Ehrenberg regarded as such 

 are molecules, having a spontaneous motion, the 

 function of which it is difficult to determine." In 

 1839 Mr. Dalrymple advocated their animal nature 

 in a communication to the Microscopical Society 

 of London, giving as his reasons the followino- 

 summary : — 



I. That while Closterium has a circulation of mole- 



Fig. 2S. — Closlcrinvi lu- 

 nula, with active granules 



